Electric meter.



Inventor",

WiHiorm J. Lloyd. m/

Abby.

PATENTED JAN; 9,

W. J. LLOYD.

ELECTRIC METER.

APPLICATION FILED MAY 10 1904 Wibnesses:

STATES WENT OFFIOE.

'WILLIAM J. LLOYD, OF PITTSFIEL'D, MASSACHUSETTS, ASSIGNOR TO STANLEY ELECTRIC MANUFACTURING COMPANY, OF PITTSFIELD, MASSACHUSETTS,- A CORPORATION OF hfEW JERSEY.

ELECTRIC METER.

Specification of Letters Patent.

Patented Jan. 9, 1906.

Application filed May 10,1904. Serial No. 207,244.

To all whom it may concern.-

Be it known that I, \VILLIAM J. LLOYD, a

citizen of the United States, residing at Pittsfield, county of Berkshire, State of Massachusetts, have invented certain new and useful Improvements in Electric Meters, of which the following is a specification.

My invention relates to meters for alternating currents of the type known as induction, in which the revolving element consists of a short-circuited conductor, such as a metal disk, the rotation of which is produced by the currents induced by stationary coils.

One feature of my invention consists in a novel arrangement of the magnetic circuit whereby efficient operation, economy in materials, and ease in assembling are obtained.

Another feature of my invention consists in a novel arrangement for producing the proper phase displacement of the flux through the disk, whereby the adjustment may be obtained with greater convenience and accuracy.

My invention will best be understood by reference to the accompanying drawings, in which Figure 1 shows a front elevation in perspective of a meter arranged in accordance with my invention, and Fig. 2 shows a back elevation in perspective of the same.

In the drawings, A represents a frame or skeleton to which all the working parts of the meter are securely attached, thereby insur ing the maintenance of perfect alinement of the parts. The frame A carries the two brackets or bearings (Z d, from which is supported the conducting-disk D. The inducing element comprises two cores B and O, both secured to the frame A. The core B is U-shaped, as shown in Fig. 2, and carries on each leg or pole a potential coil 7) b. The core 0 is C-shaped, with the addition of two intermediate poles facing the poles of core B,

and on the opposite side of the disk D.

c 0 represent two currentcoils, which are supported in grooves in core B and core O and which, coacting with the flux produced by the potential coils, cause a shifting flux and a consequent rotation of the disk in the well-understood manner. The ends of core (J extend into close proximity to the ends of core B, two small air-gaps of permanent length being maintained between the two cores by the pins i i. ith this arrangement a flux through the disk displaced approximately ninety degrees from the potential impressed upon the coils l) is obtained in the well-understood manner. For producing the exact displacement of ninety degrees the short-circuited coils g g are placed on the pole-tips of the core B. It has been customary heretofore to obtain the exact adjustment required by varying the number of turns on the short-circuited coils g g or by short-circuiting them through a variable resistance. It will be seen, however, that the position of the coils g g renders them somewhat inaccessible and makes dillicult the adjustment by means of varying the number of turns. Consequently I provide short-circuiting pieces 9 g, which may each be of a single copper strip so proportioned as to produce an overcompensation of the flux. 1 also provide the coils h h, which may be adjusted as to the number of turns and which act to return the flux through the disk to its proper phase relation. Since the coils h h occupy a more accessible position than the coils g g, they offer a much more convenient arrangement for producing the proper adjustment of the flux through the disk than can be ob tained by manipulating the coils g 9. Moreover, in some meters for certain relative proportions of the disk and of the parts of the magnetic circuit it has been found that the currents in the disk itself produce an overcompensation of the flux. In this case the short-circuited strips g 9 maybe omitted, and in both cases, Whether the overcompensation is due to the currents in the disk alone or to the conjoint influence of the currents in the disk and in the shortcircuiting strips, the short-circuited coils h h form a convenient and eflicient means for adjusting the flux through the disk to its proper phase relation.

Referring again to Fig. 1, f f represent brackets attached to frame A and adapted to support the indicating-dial and its geartrain. In Fig. 1 the indicating-dial is merely indicated in dotted lines. E represents a permanent magnet of approximately rectangular form, which is supported by the brackets e c, which are in turn supported from the frame A. The unlike poles of magnet E are both on the same side of disk D, and the magnetic circuit is completed by a magnetic member or armature e, supported on the opposite side of the disk by means of the non-magnetic support e lVith this arrangement the flux of magnet E threads the disk two times, thereby producing a strong braking action, with a compact arrangement of the magnet. Moreover, since magnet E and its armature 6 both present extended flat surfaces to the disk D a large cross-section and a low reluctance of the air-gap are obtained, thus rendering it possible to use a small drag-magnet. The braking effect can be adjusted by moving armature 6 toward or away from the surface of the disk.

I have shown and described a complete meter embodying several features, which while I prefer to use them together may with advantage be used separately and which I desire to claim whether used together or not.

What I claim as new, and desire to secure by Letters Patent of the United States, is

1. In an alternating-current meter, a U- shaped core, potential coils carried thereby, a C-shaped core having intermediate projecting poles facing the poles of the first core and its ends extending into proximity to the poles of the first core, a current-coil carried between said projecting poles, and a conducting-disk disposed between said cores.

2. In an alternating-current meter, a U- shaped core, potential coils carried thereby, a C-shaped core forming with the first core a nearly-closed magnetic circuit and having intermediate projecting poles facing the poles of the first core, a current-coil carried be tween said projecting poles, and a conducting-disk disposed between said cores.

3. In an alternating-current meter, a U- shaped core, potential coils carried on the poles thereof, a current-coil carried between said poles, a C-shaped core forming with the first core a nearly-closed magnetic circuit and having intermediate projecting poles facing the poles of the first core, a second currentcoil carried between said projecting poles, and a conducting-disk disposed between said cores.

4. In an alternating-current meter, a conducting-disk, means for producing a flux threading said disk, a magnetic member adapted to ofler a shunt-path for said fiux,

and short-circuited members subjected re through said disk and to the flux shunted.

around said disk, said members being proportioned to produce a phase displacement of the flux through said disk of ninety degrees from the phase of the potential impressed on said coils.

6. In an alternating-current meter, a U- shaped core, potential coils carried thereby, a C-shaped core forming with the first core a nearly-closed magnetic circuit and having intermediate projecting poles facing the poles of the first core, a current-coil carried be tween said projecting poles, a conductingdisk disposed between said cores, short-circuited members on the ends of the U-shaped core, and short-circuited members near th ends of the C-shaped core.

7. In an alternating-current meter, a conducting-disk, means for producing a flux threading said disk, a magnetic member adapted to offer a shunt-path for said flux, and a short-circuited member subjected to the flux through said shunt-path.

8. In an alternating-current meter, a U- shaped core, potential coils carried thereby, a Cshaped core forming with the first core a nearly-closed magnetic circuit and having intermediate projecting poles facing the poles of the first core, a conducting-disk disposed between said cores, and short-circuited members carried near the ends of said C-shaped core.

In witness whereof I have hereunto set my hand this 7th day of May, 1904.

WILLIAM J. LLOYD.

Witnesses:

SAMUEL E. WIDDIFIELD, HARRIET G. STAPLETON. 

